Efficacy and Safety of Rituximab in Autoimmune Disease-Associated Interstitial Lung Disease: A Prospective Cohort Study.

OBJECTIVES: To analyze the efficacy and safety of rituximab (RTX) in connective tissue disease associated with interstitial lung disease (CTD-ILD). METHODS: We performed a multicenter, prospective, observational study of patients with CTD-ILD receiving rituximab between 2015 and 2020. The patients were assessed using high-resolution computed tomography and pulmonary function tests at baseline, at 12 months, and at the end of follow-up. The main outcome measure at the end of follow-up was forced vital capacity (FVC) > 10% or diffusing capacity of the lungs for carbon monoxide (DLCO) > 15% and radiological progression or death. We recorded clinical characteristics, time to initiation of RTX, concomitant treatment, infections, and hospitalization. A Cox regression analysis was performed to identify factors associated with worsening ILD. RESULTS: We included 37 patients with CTD-ILD treated with RTX for a median (IQR) of 38.2 (17.7-69.0) months. At the end of the follow-up, disease had improved or stabilized in 23 patients (62.1%) and worsened in seven (18.9%); seven patients (18.9%) died. No significant decline was observed in median FVC (72.2 vs. 70.8; p = 0.530) or DLCO (55.9 vs. 52.2; p = 0.100). The multivariate analysis showed the independent predictors for worsening of CTD-ILD to be baseline DLCO (OR (95% CI), 0.904 (0.8-0.9); p = 0.015), time to initiation of RTX (1.01 (1.001-1.02); p = 0.029), and mycophenolate (0.202 (0.04-0.8); p = 0.034). Only 28 of the 37 patients (75.6%) were still undergoing treatment with RTX: two patients (5.4%) stopped treatment due to adverse events and seven patients (18.9%) died owing to progression of ILD and superinfection. CONCLUSION: Lung function improved or stabilized in more than half of patients with CTD-ILD treated with RTX. Early treatment and combination with mycophenolate could reduce the risk of progression of ILD.

Eficiencia de diferentes dosis de rituximab en la artritis reumatoide / Eficiency of different doses of rituximab in rheumatoid arthritis

OBJETIVO: Evaluar la efectividad, seguridad y coste de rituximab en pacientes con artritis reumatoide (AR) dependiendo de la dosis utilizada. MATERIAL Y MÉTODOS: Estudio observacional retrospectivo. Se incluyó a 52 pacientes con AR tratados al menos con una dosis de rituximab durante 135,3 pacientes-año. Se obtuvieron 3 grupos de tratamiento: G1, primer curso y siguientes de 2 infusiones de 1g separadas 15 días; G2, primer curso de 2 infusiones de 1g seguido por cursos de 2 infusiones de 500mg, y G3, primer curso y siguientes de 2 infusiones de 500mg separadas por 15 días. Los retratamientos fueron a demanda según la clínica. Se analizaron por grupos: el tiempo retención (Log-Rank), las tasas de retratamientos y de eventos adversos (razón de tasas de incidencia) y los costes del tratamiento por paciente-mes de rituximab. RESULTADOS: El grupo 2 mostró una mejor relación coste-efectividad que el grupo 1 ya que se asoció a una mayor retención de rituximab (media [IC del 95%] 65,7 [60,8-70,7] meses vs. 33,5 [22,7-44,3]; p < 0,001) y una menor tasa de eventos adversos graves, con solo un ligero incremento de la tasa de retratamientos (cursos/paciente-año [IC del 95%] 1,66 [1,39-1,93] vs. 1,01 [0,69.-1,34]; p = 0,005) y del coste (mediana/paciente-mes, 484,89 € vs. 473,45 €). Aunque el grupo 3 fue 41,20 €/paciente-mes más económico que el grupo 2, se asoció a una mayor tasa de retratamientos y una menor retención de rituximab (p < 0,001). CONCLUSIONES: El uso de rituximab a dosis completa al inicio seguido de dosis reducida en los sucesivos cursos administrados a demanda parece la opción más coste-efectiva

OBJECTIVE: Evaluate the effectiveness, cost and safety of rituximab in patients with rheumatoid arthritis (RA) depending on the dose used. MATERIAL AND METHODS: Retrospective observational study conducted on 52 patients with RA treated with at least one dose of rituximab for 135.3 patient-years were included. Three treatment groups were obtained: (G1) First course and following two 1g infusions separated by 15 days; (G2) First course 2 infusions of 1g followed by 2 infusions of 500mg; (G3) First course and followed by 2 infusions of 500mg separated by 15 days. Re-treatments were administered on-demand according to the clinical activity. The retention time (Log-Rank), retreats and adverse events rates (incidence rate ratio) and treatment costs per patient-month of rituximab were analysed by groups. RESULTS: Group 2 showed a better cost-effectiveness ratio than group 1, as it was associated with a longer retention of rituximab (mean [95% CI] 65.7 [60.8 to 70.7] months vs 33.5 [22.7 to 44.3]; P<.001) and a lower rate of severe adverse events with only a slight increase in the rate of retreatment (courses/patient-year [95% CI] 1.66 [1.39 to 1.93] vs. 1.01 [0.69 to 1.34]; P=.005), and in the costs (median/patient-month, €484.89 vs. €473.45). Although group 3 was €41.20/patient-month cheaper than group 2, it was associated with a higher rate of re-treatments and shorter retention of rituximab (P<.001). CONCLUSIONS: The use of full-dose rituximab at onset, followed by reduced doses in successive courses administered on-demand retreatment may be the most cost-effective option

Eficiency of different doses of rituximab in rheumatoid arthritis. / Eficiencia de diferentes dosis de rituximab en la artritis reumatoide.

OBJECTIVE: Evaluate the effectiveness, cost and safety of rituximab in patients with rheumatoid arthritis (RA) depending on the dose used. MATERIAL AND METHODS: Retrospective observational study conducted on 52 patients with RA treated with at least one dose of rituximab for 135.3 patient-years were included. Three treatment groups were obtained: (G1) First course and following two 1g infusions separated by 15 days; (G2) First course 2 infusions of 1g followed by 2 infusions of 500mg; (G3) First course and followed by 2 infusions of 500mg separated by 15 days. Re-treatments were administered on-demand according to the clinical activity. The retention time (Log-Rank), retreats and adverse events rates (incidence rate ratio) and treatment costs per patient-month of rituximab were analysed by groups. RESULTS: Group 2 showed a better cost-effectiveness ratio than group 1, as it was associated with a longer retention of rituximab (mean [95% CI] 65.7 [60.8 to 70.7] months vs 33.5 [22.7 to 44.3]; P<.001) and a lower rate of severe adverse events with only a slight increase in the rate of retreatment (courses/patient-year [95% CI] 1.66 [1.39 to 1.93] vs. 1.01 [0.69 to 1.34]; P=.005), and in the costs (median/patient-month, €484.89 vs. €473.45). Although group 3 was €41.20/patient-month cheaper than group 2, it was associated with a higher rate of re-treatments and shorter retention of rituximab (P<.001). CONCLUSIONS: The use of full-dose rituximab at onset, followed by reduced doses in successive courses administered on-demand retreatment may be the most cost-effective option.